If you had polled NFL executives at the beginning of the season about who they thought was the top running back in the NFL, Adrian Peterson would have been a unanimous choice.

But now, the sensational season of Tennessee Titans running back Chris Johnson is clouding that debate in the minds of many.

"If I had to choose one for the short term, I would pick Johnson," an NFC personnel director said this week. "He's done some pretty amazing things this year ... when you see him hit the crease and run away from the defense, you realize that there are few players in the league who can match his speed."

John Russell / Associated Press

Chris Johnson needs to average 125 yards in his final three games to become NFL's sixth 2,000-yard rusher.

Johnson, in his second NFL season, is on pace to eclipse the hallowed 2,000-yard rushing mark, and his spectacular performance has placed him in rare company in the league's record book.

Last Sunday, he became the fifth player in league history to top 2,000 scrimmage yards in his team's first 13 games, joining Jim Brown (1963), O.J. Simpson (1975), Walter Payton (1977) and Priest Holmes (2002). His eight straight 100-yard games breaks the franchise record set by Earl Campbell in 1980. If he passes the century mark again on Sunday against Miami, he will join a group tied for the third-most consecutive 100-yard games in NFL history, behind Barry Sanders (14) and Marcus Allen (11).

Johnson's chase for 2,000 yards in the final three weeks isn't that daunting. He just needs to maintain his average of 125 yards per game to eclipse the mark, and he doesn't face a single opponent with a top-10 rushing defense. Miami is ranked 13th (106.1 yards per game), San Diego 21st (117.1) and Seattle 11th (104.3)

While Johnson's blazing speed makes him a threat to take it the distance whenever he touches the ball, it has been the electrifying running skills displayed by the second-year pro that has many touting him as the premier runner in the game.

"He's special," said an AFC personnel director. "The things he can do on the field are unique."

As the most dynamic playmaker in the league, Johnson has specialized in making big plays from the backfield, and his impressive 2009 numbers validate his status. Johnson leads the league with 20 runs of 20 yards or more (Peterson is a distant second with 11), and his seven rushes covering at least 40 yards is also a league-high.

This comes on the heels of Johnson finishing as the AFC's third-leading rusher as a rookie, a feat that is even more impressive when considering Johnson spent most of 2008 splitting carries with LenDale White.

Watch NFL Network's 2010 Pro Bowl selection show on Tuesday, Dec. 29 to see who made the cut. More ...

Given Johnson's quick ascension to the top of the league, it is surprising that he was the fifth running back chosen in the 2008 draft (No. 24 overall), behind Darren McFadden (Oakland, No. 4), Jonathan Stewart (Carolina, No. 13), Felix Jones (Dallas, No. 22) and Rashard Mendenhall (Pittsburgh, No. 23). However, he had only one solid season of production during his career at East Carolina, and his inconsistencies had many viewing the speedster, who ran a blazing 4.24-second 40-yard dash at the combine, as a complementary player on the next level.

"He had shown flashes of being a dynamic player," said an NFC scout who evaluated Johnson coming out of college. "But he never put it together consistently until his senior season. ... You hoped he would develop into a big-play threat, but no one envisioned him having this kind of impact this early in his career."

Even Titans officials marvel at his explosiveness and dynamic ability.

As one Tennessee insider told me earlier in the season, "Watching him reminds me of watching great players in high school. He makes everything look so effortless, that you realize he is playing at a different speed than everyone else. ... It is like he knows he is faster than everyone else, and that has given him the kind of confidence that has made him dangerous."